It's the second one. It could turn out to be a blessing in disguise but it could also be a negative or a neutral thing.

It's surrendering yourself to fate, so it's most similar to the second one. Fate (also called providence) can be interpreted as coming from the divine or just the general, abstract, more mystical notion of the universe, the stars, an unseen order of.things, etc.

The phrases "whatever is meant to be will be," "a blessing in disguise," and "everything happens for a reason" share a similar underlying idea but may have subtle differences in interpretation. "Whatever is meant to be will be": This phrase suggests a sense of acceptance and destiny. It implies that events will unfold according to some predetermined plan or fate, and there's a certain inevitability to the outcome. "A blessing in disguise": This expression conveys the idea that even if something initially appears to be negative or unfortunate, it may turn out to be beneficial in the long run. It emphasizes the positive aspect of hidden opportunities within challenges. "Everything happens for a reason": This phrase suggests a belief that events in life, whether positive or negative, have a purpose or meaning. It implies a broader sense of order or design in the universe, where every occurrence contributes to a larger plan. While these expressions may share a common theme of acceptance and finding positive aspects in challenging situations, they can be nuanced and have varying interpretations based on individual perspectives and beliefs. Some people may use these phrases interchangeably, while others may emphasize different aspects of the underlying philosophy.

DavidK correctly gave the meaning of "a blessing in disguise" something bad happens but it then turns out to be positive for you or a person. "Whatever will be will be" refers to the concept of accepting fate. Accepting that whatever will happen was destined to happen. Or will happen to you. This is why certain people who disbelieve say make your own fate, create your own luck, stop being a dreamer.

Neither exactly. ‘A blessing in disguise’ speaks to the idea of something which seems negative turning out to have a positive result. A: It’s too bad you were fired from your job. B: Maybe it’s a blessing in disguise. I wasn’t happy doing it. ‘Everything happens for a reason’ suggests that there is a grand plan to the universe. There will be a result. Usually we would imagine this as positive, but it doesn’t state that as explicitly as the word ‘blessing’. ‘Whatever is meant to be will be’ shares the idea of the universe having a grand plan, but talks more about the event itself, and is less clearly positive.